for $1200 you have limited options. If it was me and that is all I am going to spend I would buy a savage of your liking with a twist that will be fast enough to send a larger projectile down range. Find a good stock B&C or something, have the rifle head spaced and bed the action and barrel to the new stock and you have a semicustom within your price range. I did this with my first build and it cost around $1000.

Savage actions don't have to be trued, the factory barrel it isn't bad and the accutrigger will do. The only thing is the stock are a little cheesy. I put a Bell and Carlson medalist on and had my smith skim bed the stock, lap the barrel and head space. It was a 12fvss 22-250 and it was deadly accurate.

Or double your budget and build a full custom with the components mentioned.

Doing a little more research I realized I can not afford a custom build right now. So I am thinking about adding a couple things to my current rifle making it semi custom. I know I want to get a longer and heavier barrel and probably a night force scope. Any other mod suggestions?

Does your rifle shoot now? Just save your money until you have enough to build the rifle you want. Or buy components for the build. Alot of the components are extremely long waits. You can wait 6months to a year for a rifle build. You can have alot of cash tied up for quite awhile with nothing to show for it. But I tend to pay everything up front I hate oweing people money.

I am guessing an action would be a good place to start. Which is better for a long range shooting, short or long range? And does different fluting on the bolts make a difference? Anything else to look for in an action?

JMss17:My suggestion is to work with the rifle you have now (the one in your signature Remington 700sps 7mm Rem Mag)

Have a gunsmith tune the trigger to a pull weight you like. For a deer hunting rifle where shots can come quickly and be at any range from up-close-and-personal to waaaaay over there, I like 3lbs. If it's going to be more of a long range only rifle I would say go lower ~2lbs. Cost: ~$60

Get a decent stock (HS Precision or B&C Medialist). Cost $200 to $300+

Send your rifle and new stock off to a reputable gunsmith and have a new barrel installed (caliber, contour, length - that's an entire conversion by itself) and have him true-up your action and bed it into your stock. Cost ~$650

When your rifle gets back, install the bases, rings and scope (that I assume you already have) and you're done!

I'll throw in a thought or two.
First off, I don't think it's possible to throw too much money at a barrel if you're serious about accuracy. This is even more true of a carry rifle than a bench gun (unless you shoot competition) since you won't have that extra meat to stiffen it up. Taylor the twist to the bullet you want to shoot and get the heaviest contour you can tolerate carrying.
Since this isn't a competition bench gun, I personally feel that any action, properly bedded, squared, tuned, lapped, will do the trick. Mostly, you have to have that work done on it!
Nightforce scopes are great. I have an NXS and it's wonderful. That said, I also have a Millett 6-25x56 with side focus that was about $250 delivered (close out sale from Jerry's) that will do the trick until you can afford, or find you need, better. I have a Sightron that's awesome too that can be found for $800.
I think any stock, pillar and glass bedded will fit the bill if you like how it feels. If you don't bed it, you're wasting money on a good one.
Last and IMHO, if you don't have what it takes to reload accurate ammo, I don't care how much you spend on the gun, you won't realize full potential accuracy. Competition dies, a really good priming tool, a good- square press, a good scale, taking the time to properly prep the brass and having the tools to prep it so you can load the most consistent ammo possible will make the high dollar gun worth the time and money. Oh, and did I mention custom building a load?